1. Field of the Invention
The present invention generally relates to the industrial application of inkjet-recording heads, and particularly relates to a substrate capable of forming an arbitrary pattern with an inkjet system and the manufacturing method of such substrate.
2. Description of the Related Art
A typical substrate used for semiconductor processes and soon is made from the likes of silicon. Conventionally, in order to manufacture an integrated circuit from such silicon substrate, methods such as photolithography were used. As described on pages 283 through 305 of the xe2x80x9cThin Film Handbookxe2x80x9d compiled by the Japan Society for the Promotion of Science, for example, this photolithography is a method wherein sensitive material called a resist is applied thinly on to a silicon wafer, and the integrated circuit pattern prepared on a dry glass plate with photoengraving is transcribed by being printed with light. Ion and the like are driven into the transcribed pattern to form wiring patterns and elements.
To utilize the photolithography method, however, steps such as photoengraving, resist application, exposure, developing, etc. are necessary. Thus, the production of minute patterns is not possible without semiconductor factories equipped with large devices, power distribution equipment, exhaustion equipment and the like. Accordingly, it is standard knowledge that complex process management and large costs are required in order to form minute patterns.
If, for example, an ordered pattern of xcexcm could be produced easily and inexpensively without using equipment of factories and the like, industrially, an unlimited demand could be expected. Thus, by using the inkjet system which the applicant specializes in technically, the aforementioned problems may be overcome. In other words, the inkjet-recording head that discharges ink with the inkjet system is capable of discharging from a nozzle hole an arbitrary fluid body. As the resolution of this inkjet-recording head is minute, 400 bpi for example, forming an arbitrary pattern of an ordered width of xcexcm is possible by discharging a fluid body which can be used for industrial purposes from each of the nozzle holes.
The droplets discharged from the inkjet-recording head spread up to a certain area upon reaching the surface of the substrate where the pattern is to be formed (hereinafter xe2x80x9cpattern surfacexe2x80x9d) (the motion of a single droplet reaching the subject surface is hereinafter referred to as xe2x80x9cadheringxe2x80x9d). The spreading of the adhered droplet is determined by the amount and speed of the droplet, the contact angle of the pattern surface of the fluid body and such fluid body. As a requirement therefor, the adhered fluid body pattern should not overspread and should not be discontinuous or interrupted.
In order to satisfy such requirement, the inventors of the present invention devised a substrate suitable for forming patterns with the inkjet system capable of maintaining an appropriate spread of the pattern by using surface tension, as well as the manufacturing method of such substrate.
In other words, an object of the present invention is to provide a substrate capable of forming patterns having moderate spread and continuousness by the surface tension of the fluid body upon forming patterns with the inkjet system and the like.
Another object of the present invention is to provide a manufacturing method of a substrate capable of forming patterns having moderate spread and continuousness by the surface tension of the fluid body upon forming patterns with the inkjet system and the like.
The present invention is characterized in that the substrate comprises on the base a film having a pattern portion with affinity for the fluid body. One mode of the present invention is a substrate wherein a film is formed on the base such that the base will develop affinity for the fluid body, this film is refined, and the pattern of such affinity region is selectively formed on the substrate. Moreover, in another mode, it is possible to directly form on the base a film originally having an affinity region and a non-affinity region.
A further mode of the present invention is a substrate wherein a silane coupling film is formed on the base with a silane coupling agent, and the hydrophilic region patterned on the silane coupling film comprises a polar group such as the hydroxyl group, carboxyl group, amino group, or amino carboxyl group.
Minute patterns showing hydrophilic property are formed on the entire pattern surface of the substrate. By discharging droplets of a fluid body to the pattern surface of this substrate with the inkjet system and the like, surface tension will work on the adhered droplets per hydrophilic minute pattern and prevent overspreading. As the fluid body will spread well on a hydrophilic pattern, the pattern formed by the fluid body will not be interrupted if the hydrophilic pattern is formed continuously. The shape of the pattern may be changed variously: a series of squares, a series of circles, a series of parallel lines, etc.
Here, showing xe2x80x9chydrophilic propertyxe2x80x9d shall mean that the adhesiveness to a fluid body comprising a polar group such as water is high (affinity). In other words, the contact angle against the fluid body is relatively small. Showing xe2x80x9chydrophobic propertyxe2x80x9d shall mean that the adhesiveness to a fluid body comprising a polar group such as water is low (non-affinity). In other words, the contact angle against the fluid body is relatively large. Both expressions are used for the sake of convenience as a comparison to clarify the degree of affinity against the fluid body. xe2x80x9cFluid bodyxe2x80x9d is not limited to ink, but may be any medium which may be used industrially and comprises a viscosity (several cp) capable of being discharged from the nozzle. That is, it does not matter whether it is hydrophilic or hydrophobic. Nor does it matter whether it is organic or inorganic. Moreover, a mixture may be mixed in the fluid body in a colloidal form.
The affinity region may be structured by a hydrophilic region being patterned on to a hydrophobic region, or a hydrophobic region being patterned on to a hydrophilic region.
Another mode of the present invention is a substrate comprising a hydrophilic film showing hydrophilic property formed with a prescribed pattern on a pattern surface showing hydrophobic property, wherein this hydrophilic film is composed of inorganic oxide such as silica or alumina.
The substrate showing the aforementioned hydrophobic property, for example, is formed from one among bakelite, polyester, polyethylene, tefron, PMMA, polypropylene, and chloroethylene.
The present invention is a substrate comprising a copolymer compound film composed of a monomer showing hydrophilic property and a monomer showing hydrophobic property. For example, the monomer showing hydrophilic property is ethylene and the monomer showing hydrophobic property is vinyl alcohol.
The present invention is a method of manufacturing a substrate with a pattern showing hydrophilic property formed on a pattern surface comprising the steps of (a) applying a silane coupling agent to the pattern surface of the base and forming a silane coupling film, (b) forming a mask conforming to the pattern to be provided on the silane coupling film, and (c) activating the silane coupling film provided with the mask by applying energy thereto in order to generate a polar group. In the activating step, for example, the silane coupling agent is activated by ultraviolet irradiation or corona discharge.
The present invention is a method of manufacturing a substrate with a pattern showing hydrophilic property formed on a pattern surface comprising the steps of forming an organic mask conforming to the pattern to be provided on the pattern surface, forming an in organic oxide film on the pattern surface provided with the in organic mask, and removing the organic mask on the pattern surface with the in organic oxide film formed thereon and simultaneously removing the in organic oxide film selectively.
The present invention is a method of manufacturing a substrate with a pattern showing hydrophobic property formed on a pattern surface comprising the steps of forming an organic mask conforming to the pattern to be provided on the pattern surface, forming an in organic oxide film on the pattern surface provided with the in organic mask, removing the organic mask on the pattern surface with the in organic oxide film formed thereon and simultaneously removing the in organic oxide film selectively, and processing the surface of the remaining in organic oxide film to be hydrophilic.